What Should Pluto's Smallest Moons Be Called?

This week, the SETI Institute launched a Web site, translated into 12 languages, that invites visitors to submit and vote on names for Pluto's two smallest moons, currently known as P4 and P5. In case you're thinking of various celebrities or body parts, think again: International Astronomical Union conventions stipulate that "the names must be mythological and related to the dominion of Hades." Pluto's three other moons -- Charon, Hydra, and Nix -- all meet these criteria. P4 and P5 were discovered in 2011 and 2012 respectively.

What's the Big Idea?

It's the first time the public has been invited to name a planet's moons, and the gesture ties back to how Pluto itself got its name: An eleven-year-old girl offered it after its discoverer, Clyde Tombaugh, asked for suggestions in 1930. SETI astronomer Mark Showalter says, "I like to think that we are doing honor to Tombaugh’s legacy by now opening up the naming of Pluto’s two tiniest known moons to everyone." NASA's New Horizons spacecraft is scheduled to be in Pluto's neighborhood -- and start beaming back pictures -- in early 2015.